Accompanying with thickness reductions and weight reductions of electronic devices, such as display panels, solar cells and thin-film secondary batteries, there is a demand for reducing thickness of a substrate (a first substrate), such as a glass plate, a resin plate and a metal plate used in those electronic devices.
However, when the thickness of the substrate is reduced, a handling property of the substrate deteriorates, and therefore it becomes difficult to form a functional layer (a thin film transistor (TFT), a color filter (CF)) used in an electronic device on a surface of the substrate.
Accordingly, a manufacturing method of an electronic device in which a functional layer is formed on a surface of a substrate in a state where a reinforcing plate (a second substrate) is laminated on a back surface of the substrate to configure a laminate has been proposed. In this manufacturing method, since the handling property of the substrate is enhanced, the functional layer can be favorably formed on the surface of the substrate. The reinforcing plate is peeled off from the substrate after the formation of the functional layer (for example, Patent Document 1).
The peeling method of the reinforcing plate disclosed in Patent Document 1 is performed by bending deformation of a reinforcing plate, or a substrate, or both of them in a direction to separate them from each other along a peeling proceeding direction from one end portion side toward the other end portion side of two corners located on a diagonal line of a rectangular-shaped laminate. A plurality of movable bodies fixed on a flexible plate is independently moved while one of the reinforcing plate and the substrate is held by the flexible plate and the other thereof is held by a holding member, and the flexible plate is subjected to bending deformation along the peeling proceeding direction. In this manner, this bending deformation is performed.
The peeling device disclosed in Patent Document 1 has one or three servo cylinders for bending deformation of the flexible plate. The longitudinal axis of the servo cylinder is arranged along the peeling proceeding direction, and a tip end portion of a piston of the servo cylinder is supported on one end portion side of the flexible plate. When the piston of the servo cylinder is towed, the power is transmitted to the one end portion side of the flexible plate, the flexible plate starts bending deformation, and an interface between the substrate and the reinforcing plate is peeled off due to bending moment caused by continuous bending deformation of the flexible plate.
Patent Document 2 discloses a peeling device for peeling off a flexible film such as a plastic film from a reinforcing plate.
The peeling device disclosed in Patent Document 2 has a mounting table for holding a non-sticking surface of a flexible film substrate (a laminate of the flexible film and the reinforcing plate), and a peeling unit which peels off the reinforcing plate from the flexible film.
The peeling unit includes a rotating body having a holding portion which holds the reinforcing plate, a rotating member which rotates the rotating body, a frame which rotatably holds the rotating body in a cantilever manner, and a moving member which moves the frame. In addition, a holding surface of the holding portion is a curved surface so as to hold the reinforcing plate in a curved manner.
In the peeling method of the reinforcing plate by the peeling device disclosed in Patent Document 2, the flexible film of the flexible film substrate is adsorbed and held on the mounting table. Next, the frame is horizontally moved by the moving member and the rotating body is rotated by the rotating member such that a start point of the holding portion of the peeling unit is positioned directly above the one end side of the reinforcing plate. Thereafter, the mounting table is moved upward toward the holding portion, and one end side of the reinforcing plate and the start point of the holding portion are in contact with each other under a predetermined pressure. Thereafter, the one end side of the reinforcing plate is adsorbed and held on the start point of the holding portion, the frame is horizontally moved to the other side by the moving member, and the rotating body is rotated by the rotating member. Thus, the reinforcing plate is peeled off from the flexible film while being sequentially bent from one end side toward the other end side of the reinforcing plate.